sdkconfig.defaults

# Project-wide sdkconfig overrides for microreader2.
# These values are merged into the generated sdkconfig.<env> on build.

CONFIG_ESPTOOLPY_FLASHSIZE_16MB=y
CONFIG_ESPTOOLPY_FLASHSIZE="16MB"

# Enable FAT Long File Name support (needed for .epub filenames)
CONFIG_FATFS_LFN_HEAP=y

# Build a per-file cluster-link map so fseek() stays in RAM instead of
# re-traversing the FAT chain on every random access. ~29% faster conversion.
CONFIG_FATFS_USE_FASTSEEK=y
CONFIG_FATFS_USE_LABEL=y

# Main task needs enough stack for EPUB parsing (ZIP + XML + CSS) and
# for FatFS/SDSPI calls inside settings flows (clear cache, etc).
# IDF default is 3584 which is far too tight.
CONFIG_ESP_MAIN_TASK_STACK_SIZE=16384

# --- RAM optimizations ---
# Optimize for performance (-O2) — faster CPU-bound inflate/XML parsing
CONFIG_COMPILER_OPTIMIZATION_PERF=y
CONFIG_COMPILER_OPTIMIZATION_DEBUG=n

# Use newlib nano printf (smaller code, no float support needed)
CONFIG_NEWLIB_NANO_FORMAT=y

# Move FreeRTOS functions to flash (slightly slower, saves IRAM)
CONFIG_FREERTOS_PLACE_FUNCTIONS_INTO_FLASH=y

# Use SPI flash ROM implementation (saves IRAM by using ROM code)
CONFIG_SPI_FLASH_ROM_IMPL=y

# Reduce ISR stack (default 1536, we have no heavy ISRs)
CONFIG_FREERTOS_ISR_STACKSIZE=1024

# Move heap allocator (tlsf) from IRAM to flash — saves ~3.5KB IRAM
CONFIG_HEAP_PLACE_FUNCTION_INTO_FLASH=y

# SPI master/slave ISR in flash — we don't do SPI during flash writes
CONFIG_SPI_MASTER_ISR_IN_IRAM=n
CONFIG_SPI_SLAVE_ISR_IN_IRAM=n

# No need to post events from IRAM ISR context
CONFIG_ESP_EVENT_POST_FROM_IRAM_ISR=n

# Reduce HAL assertions (silent = no format strings in IRAM)
CONFIG_HAL_DEFAULT_ASSERTION_LEVEL=1

# Move libc lock functions to flash
CONFIG_LIBC_LOCKS_PLACE_IN_IRAM=n

# --- Internal task stack reductions (heap savings) ---
# We don't use esp_timer callbacks or event loops heavily
CONFIG_ESP_TIMER_TASK_STACK_SIZE=2048
CONFIG_ESP_SYSTEM_EVENT_TASK_STACK_SIZE=2048